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Handheld GPS - global positioning system - unit
keeps track of your whereabouts.
THERE I was, descending the Big Island's hellish Mauna Loa Trail with two very sore and throbbing large toes, when at about 9,000 feet a dense rain cloud enveloped me, reducing visibility to about 10 feet. Where in the world are you?
What had been a pretty well marked trail over indistinguishable pahoehoe lava now disappeared in the mist. I reached in my backpack for the Magellan GPS 2000 hand-held navigation device.
In a few minutes I fixed my position from passing satellites, then continued walking on what I thought was the trail. About 30 minutes later with the cloud having grown thicker I found myself standing on the brink of a steep lava cliff.
Again, I got the GPS, fixed my position, then called up a map on the tiny screen that showed the route I had taken. I back-tracked using the GPS as a guide until I was back where I zigged when I should have zagged.
Hand-held navigation systems, known as GPS - global positioning system - utilize a sophisticated satellite system that can pinpoint your location and plot your journeys on a small screen.
GPS is a constellation of 24 navigation satellites orbiting about 12,000 feet above the earth. The precise time and position information transmitted by these satellites is used by the GPS receiver to compute a position fix.
How accurate is GPS? How about 25 meters or better!
These things used to cost in the thousands of dollars. But prices for basic models have tumbled, making them popular with fishermen wanting to map their favorite fishing spot, hikers plotting a route, even some urbanites just trying to find their cars in a mall parking lot.
Magellan GPS 2000, designed for outdoor and sports recreation, comes with EZstar initialization to fix your main location fast and easy, allows 200 locations to be saved in its memory, has a real time track plotter, five reversible routes with up to 20 legs each, sunrise/ sun set/ lunar calculations, and resettable trip odometer. It sells for $150.
The new GPS 2000 XL, $190, has all the above mentioned enhancements, but comes in a "ruggedized" version: rubber armoring, wraparound grips, a new keypad and brighter display.
By Tim Ryan